diff options
| -rw-r--r-- | drivers/spi/spi-omap2-mcspi.c | 181 |
1 files changed, 150 insertions, 31 deletions
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 0c73dd4f43a..9fdb7a9ae03 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -20,6 +20,8 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ +#define USE_DMA_ENGINE_RX +#define USE_DMA_ENGINE_TX #include <linux/kernel.h> #include <linux/init.h> @@ -28,6 +30,8 @@ #include <linux/device.h> #include <linux/delay.h> #include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/omap-dma.h> #include <linux/platform_device.h> #include <linux/err.h> #include <linux/clk.h> @@ -93,6 +97,8 @@ /* We have 2 DMA channels per CS, one for RX and one for TX */ struct omap2_mcspi_dma { + struct dma_chan *dma_tx; + struct dma_chan *dma_rx; int dma_tx_channel; int dma_rx_channel; @@ -300,6 +306,30 @@ static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) return 0; } +static void omap2_mcspi_rx_callback(void *data) +{ + struct spi_device *spi = data; + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + complete(&mcspi_dma->dma_rx_completion); + + /* We must disable the DMA RX request */ + omap2_mcspi_set_dma_req(spi, 1, 0); +} + +static void omap2_mcspi_tx_callback(void *data) +{ + struct spi_device *spi = data; + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + complete(&mcspi_dma->dma_tx_completion); + + /* We must disable the DMA TX request */ + omap2_mcspi_set_dma_req(spi, 0, 0); +} + static unsigned omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) { @@ -314,6 +344,9 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) u8 * rx; const u8 * tx; void __iomem *chstat_reg; + struct dma_slave_config cfg; + enum dma_slave_buswidth width; + unsigned es; mcspi = spi_master_get_devdata(spi->master); mcspi_dma = &mcspi->dma_channels[spi->chip_select]; @@ -321,6 +354,71 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; + if (cs->word_len <= 8) { + width = DMA_SLAVE_BUSWIDTH_1_BYTE; + es = 1; + } else if (cs->word_len <= 16) { + width = DMA_SLAVE_BUSWIDTH_2_BYTES; + es = 2; + } else { + width = DMA_SLAVE_BUSWIDTH_4_BYTES; + es = 4; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; + cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; + cfg.src_addr_width = width; + cfg.dst_addr_width = width; + cfg.src_maxburst = 1; + cfg.dst_maxburst = 1; + + if (xfer->tx_buf && mcspi_dma->dma_tx) { + struct dma_async_tx_descriptor *tx; + struct scatterlist sg; + + dmaengine_slave_config(mcspi_dma->dma_tx, &cfg); + + sg_init_table(&sg, 1); + sg_dma_address(&sg) = xfer->tx_dma; + sg_dma_len(&sg) = xfer->len; + + tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1, + DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (tx) { + tx->callback = omap2_mcspi_tx_callback; + tx->callback_param = spi; + dmaengine_submit(tx); + } else { + /* FIXME: fall back to PIO? */ + } + } + + if (xfer->rx_buf && mcspi_dma->dma_rx) { + struct dma_async_tx_descriptor *tx; + struct scatterlist sg; + size_t len = xfer->len - es; + + dmaengine_slave_config(mcspi_dma->dma_rx, &cfg); + + if (l & OMAP2_MCSPI_CHCONF_TURBO) + len -= es; + + sg_init_table(&sg, 1); + sg_dma_address(&sg) = xfer->rx_dma; + sg_dma_len(&sg) = len; + + tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1, + DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (tx) { + tx->callback = omap2_mcspi_rx_callback; + tx->callback_param = spi; + dmaengine_submit(tx); + } else { + /* FIXME: fall back to PIO? */ + } + } + count = xfer->len; c = count; word_len = cs->word_len; @@ -342,7 +440,7 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) element_count = count >> 2; } - if (tx != NULL) { + if (tx != NULL && mcspi_dma->dma_tx_channel != -1) { omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel, data_type, element_count, 1, OMAP_DMA_SYNC_ELEMENT, @@ -357,7 +455,7 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) xfer->tx_dma, 0, 0); } - if (rx != NULL) { + if (rx != NULL && mcspi_dma->dma_rx_channel != -1) { elements = element_count - 1; if (l & OMAP2_MCSPI_CHCONF_TURBO) elements--; @@ -377,12 +475,18 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) } if (tx != NULL) { - omap_start_dma(mcspi_dma->dma_tx_channel); + if (mcspi_dma->dma_tx) + dma_async_issue_pending(mcspi_dma->dma_tx); + else + omap_start_dma(mcspi_dma->dma_tx_channel); omap2_mcspi_set_dma_req(spi, 0, 1); } if (rx != NULL) { - omap_start_dma(mcspi_dma->dma_rx_channel); + if (mcspi_dma->dma_rx) + dma_async_issue_pending(mcspi_dma->dma_rx); + else + omap_start_dma(mcspi_dma->dma_rx_channel); omap2_mcspi_set_dma_req(spi, 1, 1); } @@ -406,7 +510,10 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE); omap2_mcspi_set_enable(spi, 0); + elements = element_count - 1; + if (l & OMAP2_MCSPI_CHCONF_TURBO) { + elements--; if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) & OMAP2_MCSPI_CHSTAT_RXS)) { @@ -725,32 +832,12 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data) { - struct spi_device *spi = data; - struct omap2_mcspi *mcspi; - struct omap2_mcspi_dma *mcspi_dma; - - mcspi = spi_master_get_devdata(spi->master); - mcspi_dma = &(mcspi->dma_channels[spi->chip_select]); - - complete(&mcspi_dma->dma_rx_completion); - - /* We must disable the DMA RX request */ - omap2_mcspi_set_dma_req(spi, 1, 0); + omap2_mcspi_rx_callback(data); } static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data) { - struct spi_device *spi = data; - struct omap2_mcspi *mcspi; - struct omap2_mcspi_dma *mcspi_dma; - - mcspi = spi_master_get_devdata(spi->master); - mcspi_dma = &(mcspi->dma_channels[spi->chip_select]); - - complete(&mcspi_dma->dma_tx_completion); - - /* We must disable the DMA TX request */ - omap2_mcspi_set_dma_req(spi, 0, 0); + omap2_mcspi_tx_callback(data); } static int omap2_mcspi_request_dma(struct spi_device *spi) @@ -758,17 +845,43 @@ static int omap2_mcspi_request_dma(struct spi_device *spi) struct spi_master *master = spi->master; struct omap2_mcspi *mcspi; struct omap2_mcspi_dma *mcspi_dma; + dma_cap_mask_t mask; + unsigned sig; mcspi = spi_master_get_devdata(master); mcspi_dma = mcspi->dma_channels + spi->chip_select; + init_completion(&mcspi_dma->dma_rx_completion); + init_completion(&mcspi_dma->dma_tx_completion); + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); +#ifdef USE_DMA_ENGINE_RX + sig = mcspi_dma->dma_rx_sync_dev; + mcspi_dma->dma_rx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + if (!mcspi_dma->dma_rx) { + dev_err(&spi->dev, "no RX DMA engine channel for McSPI\n"); + return -EAGAIN; + } +#else if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX", omap2_mcspi_dma_rx_callback, spi, &mcspi_dma->dma_rx_channel)) { dev_err(&spi->dev, "no RX DMA channel for McSPI\n"); return -EAGAIN; } +#endif +#ifdef USE_DMA_ENGINE_TX + sig = mcspi_dma->dma_tx_sync_dev; + mcspi_dma->dma_tx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + if (!mcspi_dma->dma_tx) { + dev_err(&spi->dev, "no TX DMA engine channel for McSPI\n"); + dma_release_channel(mcspi_dma->dma_rx); + mcspi_dma->dma_rx = NULL; + return -EAGAIN; + } +#else if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX", omap2_mcspi_dma_tx_callback, spi, &mcspi_dma->dma_tx_channel)) { @@ -777,9 +890,7 @@ static int omap2_mcspi_request_dma(struct spi_device *spi) dev_err(&spi->dev, "no TX DMA channel for McSPI\n"); return -EAGAIN; } - - init_completion(&mcspi_dma->dma_rx_completion); - init_completion(&mcspi_dma->dma_tx_completion); +#endif return 0; } @@ -812,8 +923,8 @@ static int omap2_mcspi_setup(struct spi_device *spi) list_add_tail(&cs->node, &ctx->cs); } - if (mcspi_dma->dma_rx_channel == -1 - || mcspi_dma->dma_tx_channel == -1) { + if ((!mcspi_dma->dma_rx && mcspi_dma->dma_rx_channel == -1) || + (!mcspi_dma->dma_tx && mcspi_dma->dma_tx_channel == -1)) { ret = omap2_mcspi_request_dma(spi); if (ret < 0) return ret; @@ -848,6 +959,14 @@ static void omap2_mcspi_cleanup(struct spi_device *spi) if (spi->chip_select < spi->master->num_chipselect) { mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + if (mcspi_dma->dma_rx) { + dma_release_channel(mcspi_dma->dma_rx); + mcspi_dma->dma_rx = NULL; + } + if (mcspi_dma->dma_tx) { + dma_release_channel(mcspi_dma->dma_tx); + mcspi_dma->dma_tx = NULL; + } if (mcspi_dma->dma_rx_channel != -1) { omap_free_dma(mcspi_dma->dma_rx_channel); mcspi_dma->dma_rx_channel = -1; |